Pipelines that are used to transport slurries (water and solids) need to be protected against internal erosion, particularly when certain types of slurries are being transported. A known method of effecting protection against erosion is to line the pipe joints internally with a urethane elastomer, natural rubber, or other abrasion resistant plastic material, in thicknesses that range from 0.25 inches to more than 1.00 inch. The customary practice has been to line the pipe in a shop in lengths of 10 to 40 feet or more, and to utilize welded-on flanges at the pipe ends to enable them to be joined together in the field to construct a pipeline. To prevent damage to the internal urethane coating due to the heat effects of welding, the flanges are welded to the pipe ends prior to application of the internal coating. Thus, prior practices did not permit field welding of individually lined pipe sections, which is a much more desirable procedure than the practices outlined above, and required the use of flanges which are expensive and time consuming to install.
The present invention provides a new and improved process and apparatus for internally coating pipes without the use of flanges and permitting field welding of individually lined pipe sections in order to construct a pipeline. This is accomplished by lining the weldment areas of the pipeline after welding is completed.